Self‐Poled Sausage‐Like PVDF Nanowires Produced by Confined Phase Inversion as Novel Piezoelectric Nanogenerators

Abstract

Piezoelectric poly(vinylidene fluoride) (PVDF) nanowires are of particular interest for energy harvesting as they are ultra‐sensitive to small vibrations. Here, a new, cost‐effective, and scalable approach to producing PVDF nanowires with strongly enhanced power output is presented. The method combines template‐wetting in cylindrical nano‐confinement with anisotropic solvent‐nonsolvent phase inversion to yield a fully novel nanowire morphology consisting of “sausage‐like” strings of nano‐domains. Dynamic numerical simulations of the phase inversion reveal the formation of these structures to be subject to a very rich and complex phenomenology. The simulated dependence of the feature size on the degree of confinement agrees with the experimentally observed trend. It is unambiguously demonstrated that the sausage‐like nano‐generators upsurge the power density to 280% compared to normal nanowires. Finite element modeling explains how the higher deformability of the sausage‐like nanostructures gives rise to this significant enhancement in piezoelectric performance.

Development of Porous Polyacrylonitrile Composite Fibers: New Precursor Fibers with High Thermal Stability

“…Among various polymer fiber fabrication techniques, wet spinning and electrospinning have been the most frequently applied methods in the recent years [6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22]. Known as a primary method, wet spinning has been employed to prepare a significant majority of PAN fibers [23][24][25][26].…”

Recent progress on polyvinylidene difluoride-based nanocomposites: applications in energy harvesting and sensing

“…Soleymani et al 215 synthesized the sausage-like PVDF nanowire by template wetting methods and shows their enhanced nanogenerator performance than up to 280% compared to simple PVDF nanowires, which are due to the deformed morphology of sausage-like PVDF. They found an open circuit voltage of 3.12 V and a short circuit current of 1.36 A with sausage-like PVDF nanogenerators, as shown in Fig.…”

“…25c. 215 By Ag and ZnO doping, Zhou et al 216 increased the b phase content and microspores in P(VDF-TrFE), which is attributed to the enhanced piezoelectric performance of the composites. The nanogenerator based on this composite attains a power density up to 7.1 mW cm À2 and is able to convert even weak physiological signals to electricity.…”

Progress in Piezoelectric Nanogenerators Based on PVDF Composite Films

“…In contrast, piezoelectric polymers possess outstanding characteristics such as good flexibility, light weight, no toxicity, and easy processing [20][21][22][23]. Among them, poly(vinylidene fluoride) (PVDF) is a very promising piezoelectric polymer with long-term stability under a high electric field [24][25][26][27]. PVDF is a kind of semi-crystalline polymer, which mainly crystallizes into five different phases, i.e., α, β, γ, δ, and ε [28,29].…”